1. Field of the Invention
The present invention relates to information handling systems, and more particularly to information handling systems including a graphic workstation having the capability of processing graphics data and image data for display on a single display monitor.
2. Prior Art
The idea of having a copy of the original image in the terminal is not new. The image processor in the IBM-7350 image display and processing terminal uses special purpose memories (called band buffers) to store image data. However, because it has a single frame buffer its "real"time interactive capability is limited to operations on the frame buffer content. These operations are implemented on the video path and consist basically in image zoom, image roam, and VLUT (Video Look-Up Table) manipulation.
The use of double frame buffers is standard in high performance graphics terminals such as the IBM-5085. No interactive image display capability is provided.
None of the prior art known to the inventor hereof teaches the concept of combining image data at sub-video rate into a frame buffer with a word length smaller than the number of bits used in the original image to represent each pixel, and making use of a double buffer to allow the implementation of interactive image display functions as those described.
U.S. Pat. No. 4,484,187 shows a video overlay system having interactive color addressing which includes two refresh buffers, each four bits deep, with outputs to a look-up table, with two additional bits stored in special registers to be combined with the eight bits from the buffers to address the look-up table while operating at video scan rates. The purpose of the patent is to provide a depth effect by moving one image over another. The patent does not show a graphics workstation for displaying image and graphics data including among other things a graphics data processing means and an image data processing means.
U.S. Pat. No. 4,439,760 shows method and apparatus for compiling three-dimensional depth digital image information. The invention deals primarily with the implementation of a depth sorting algorithm on a video bus when data are transferred from a set of video memories to a look-up table. The patent does not teach or suggest a graphics workstation for displaying both image and graphics data which includes among other things a graphics data processing means and an image data processing means.
U.S. Pat. No. 4,200,869 shows a data display control system with plural refresh memories. The invention primarily relates to the display character data. The contents of two frame buffers operating at a video rate and containing character data are conditionally displayed under control of a display control bit in each of the buffers. Image superposition and shifting is achieved via corresponding start address registers in the time control circuit which generates the same buffer addresses.
As with the prior art described above, the patent does not teach a graphics workstation for displaying both image and graphics data which includes among other things a graphics data processing means and an image data processing means.
U.S. Pat. No. 4,447,882 shows method and apparatus for reducing graphics patterns coded by binary characters and represented in rows and columns of a prescribed grid. As with the prior art discussed above, the patent does not teach a graphics workstation where displaying both image and graphics data which includes a graphics data processing means and an image data processing means.
U.S. Pat. No. 4,360,884 relates to apparatus for displaying a plurality of fundamental figures each defined by a preset number of vectors on a display device of the raster scanning type. The patent describes a display device to display polygon shaped figures given the edges end points plus edge gradient information. It employs video line buffers for storage.
The patent does not teach nor suggest a graphics workstation for displaying both image and graphics data including a graphics data processing means and an image data processing means.
U.S. Pat. No. 4,528,634 relates to a bit pattern generator including a mask pattern checking system based on the mask being verified being scanned, comparing the scanned image to the output of a bit pattern generator (a reference image) and detecting any discrepancy between the scanned and the referenced image.
As with the prior art described above, the patent does not teach a graphics workstation for displaying both image and graphics data which includes among other things a graphics data processing means and an image data processing means.
U.S. Pat. No. 4,367,466 describes a display control apparatus for a character oriented display. It used double line buffers in which characters to be displayed are stored in a coded form as opposed to a pixel all points addressable form.
As with the prior art described above, the patent does not teach a graphics workstation for displaying both image and graphics data which includes among other things a graphics data processing means and an image data processing means.